The light cycle was fixed at 12 hours. Two animals in group 1, one in group 2 and two in group 3 died during the follow- up period (one during surgery) so 46 rats with 92 femur were evaluated finally. All animals in this study were sacrificed Tipifarnib cancer at 14th week by using high dose of ketamine. Bone densitometry At the baseline and 14 week later, bone mineral density (BMD) of the femurs were measured in vivo under anesthesia with a dual-energy X-ray absorptiometer (Norland XR-36) using the small-animal software in each rat. Initially 51 rats with 102 femurs were evaluated while 46 rats with 92 femurs were measured at the end of 14 weeks. In all measurements the animals were placed in a supine position with a complete abduction of the hind limbs and each analysis was performed by the same researcher.
The instrument was calibrated daily. The scan images were analyzed and BMD (in grams per square centimeter) (gr/cm 2 ) of the metaphyseal zone of proximal femurs were determined. Statistical analysis Each mouse had its BMD evaluated separately in twelve subgroups for the right and left femurs regarding to mean baseline and final (14th week). Mean and standard deviation (SD) were calculated for descriptive statistics of continuous variables and median values for discrete variables. Kolmogorov-Smirnov test was used to analyse the normality of data. The means of groups were analyzed by using ANOVA. Post hoc Bonferroni’s multiple comparison procedure was used to determine which values were significantly different. Paired t-tests were used to compare means for BMD data between the subgroups.
Two tailed hypothesis was considered in the analyses and a significant difference was accepted while p��0.05. SPSS 15.0 Software for Windows (SPSS Inc., Chicago, IL, USA) was used in the evaluation of statistical analysis. RESULTS The mean BMDs at the beginning and final follow-up of right and left femurs of all animals as show in Figure 1. There was no statistically significant difference between the groups with respect to baseline BMD of right and left femurs (p = 1,000 and p = 0,788 respectively). With respect to 14th week BMD of the right femurs, there was statistically differences between the groups (p=0,000). Bonferroni test showed the difference was sourced from group 1 when compared with the others while there was no statistically significant difference between groups 2 and 3 (p =0,256).
The mean BMD results of the left femurs in group 3 were statistically lower than the results in groups 1 and 2 at the time of 14th week. The statistically GSK-3 significance results of all subgroups were given in Table 1. Figure 1 Mean baseline and 14(th) weeks bone mineral densitometry values of rats in control, Botulinum Toxin-A injected and ovariectomized groups. Table 1 Statistical differences between subgroups obtained by Paired t-tests. DISCUSSION BMD’ decrease after ovariectomy is expected in both femurs.